The killing of black Florida teenager Trayvon Martin has sparked a weird kind of racial spasm that's resulted in terrible articles, Spike Lee scaring old people, and made Facebook almost unvisitable for the past week. Now Metro Detroit's getting in on the bile after someone in Dearborn — the suburb of Detroit home to Ford Motor Company — reprogrammed an electronic construction sign to proclaim "Trayvon A N****R", although probably without the asterisks.